Showing posts with label Divisions. Show all posts
Showing posts with label Divisions. Show all posts

Sunday, March 20, 2011

Division Alignment Problems

I'm no fan of the current division alignment in major league baseball.  Each league has a different number of teams, and there are three sizes of divisions.  When MLB went to the current three-division alignment in 1994, each league had 14 teams arranged in divisions, one with four teams and two with five.  With the 1998 expansion, each league added a team and the Brewers moved from the AL to the NL.  The AL now has 14 teams and the NL 16.  The AL has division sizes of 4, 5 and 5, while the NL has sizes of 5, 6 and 5.

This poses a bit of a problem for the post season picture.  It is easier to win a division with fewer teams in that division, in terms of straight odds.  And it is also easier to finish second in that division and have a shot at the wildcard.  Now for some geeky math.  The odds of a team winning its division are 1/x, where x is the number of teams in that division.  That's obvious.  But the odds of finishing in second place is also 1/x.  Since there are three divisions, the odds of making the playoffs by finishing second (wildcard) are 1/3 of 1/x, or 1/3x.  The odds of a team making the playoffs are the odds of winning the division plus the odds of winning the wildcard.  So, that would equal 1/x + 1/3x, or 3/3x + 1/3x = 4/3x, with x being the number of teams in that division.  For teams in a four-team division, the odds are 4/3(4) = 1/3, or 0.333.  For teams in a five-team division they are 4/3(5) = 4/15, or 0.267.  For teams in a six-team division they are 4/3(6) = 4/18, or 2/9, or 0.222.

Making the playoffs gives each team (roughly) the same odds of winning the World Series.  So, for teams in a four-team division, the simple random odds of winning the WS are 50% greater than those teams in a six-team division.  Is this what baseball wants?  I think it better to balance the number of teams in each division, even if it means screwing up interleague play, than to create artificial favorites.